Investments Ownership Positions in Significant Unconsolidated (Details)	Dec. 31, 2017	Dec. 31, 2016	Feb. 01, 2016	Dec. 31, 2015
Windfield Holdings
Schedule of Equity Method Investments [Line Items]
Ownership percentage	49.00%	49.00%		49.00%
Nippon Aluminum Alkyls
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%		50.00%
Magnifin Magnesiaprodukte GmbH & Co. KG
Schedule of Equity Method Investments [Line Items]
Ownership percentage	0.00%	0.00%	50.00%	50.00%
Nippon Ketjen Company Limited
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%		50.00%
Eurecat S.A.
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%		50.00%
Fabrica Carioca de Catalisadores S.A.
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%		50.00%